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1.
乙烯(ET)信号在植物抵抗各种逆境反应中具有重要作用,但目前关于乙烯信号在调控水稻纹枯病抗性中的作用仍缺乏系统研究。本研究以感纹枯病水稻品种Lemont和抗纹枯病水稻品种YSBR1为材料,分析了纹枯病菌接种后乙烯合成关键基因及信号传导途径中标志基因的表达水平,结果显示,纹枯病菌侵染可显著诱导相关基因的表达、激活乙烯信号。进一步采用乙烯合成抑制剂和信号激活剂处理水稻并进行接种鉴定,结果显示,两种化学剂分别可抑制或激活乙烯信号;无论是Lemont还是YSBR1,激活其乙烯信号均可显著增强抗病性,而抑制该信号均显著降低抗病性。对3个乙烯受体突变体(ethylene response2, etr2; ethylene response3, etr3; ethylene response sensor2, ers2)进行温室接种鉴定,发现突变体的病斑长度均极显著高于野生型对照。以上研究表明乙烯信号在水稻对纹枯病菌的防卫反应或基础抗性中具有十分重要的作用,结果将为进一步解析“水稻-纹枯病菌”间的互作机制、制定合适的病害综合防控策略提供理论基础。 相似文献
2.
水稻纹枯病寄主-病原物互作鉴别品种与菌株的筛选 总被引：6，自引：0，他引：6
经过近十年的病原菌接种试验,从国内外数百份水稻种质中,筛选出了抗病水平不同的5个代表品种Lemont、武育粳3号、Jasmine85、C418和YSBR1,作为水稻纹枯病菌致病力的鉴别品种。从江苏、广东、广西、海南、云南、湖南、福建等省采集、分离的水稻纹枯病菌中,初步筛选出致病力有差异的30个菌株,于温室苗期接种上述5个品种,确定了不同致病力的5个代表菌株C30、GD-118、E67、YN-7和YN-3。将选出的品种和菌株在江苏扬州和浙江富阳进行大田成株期抗性和致病力分析,结果表明:品种的抗病性和菌株的致病力都存在极显著差异,分别属于5个和3个不同的显著性级别,均可暂时作为鉴定材料使用。据以上结果,初步建立了一套可供水稻纹枯病菌致病力检测和寄主抗病性鉴定的鉴别体系。本文还讨论了建立水稻纹枯病鉴别体系的必要性、可行性和需要进一步开展的工作。 相似文献
3.
植物病原真菌对甲基立枯磷的抗药性及风险研究 总被引：5，自引：2，他引：3
通过对人工获得的抗甲基立枯磷菌株的抗药水平、在培养基上的生长速度、致病力、对其它杀菌剂的敏感性测定以及对菌核的观察和用药条件等方面分析, 在实验室内进行了植物病原真菌对甲基立枯磷的抗药性风险研究。结果显示, 不同的病原菌具有不同的抗药性。抗甲基立枯磷的水稻纹枯病菌菌株对甲基立枯磷的抗药性较强、抗药性风险大; 小麦纹枯病菌和油菜菌核病菌抗药菌株抗药性较弱、风险小。抗甲基立枯磷的水稻纹枯病菌对菌核净具有高水平正交互抗性; 抗甲基立枯磷的小麦纹枯病菌对菌核净和扑海因有中等程度正交互抗性; 这两种真菌的抗药菌株对五氯硝基苯的正交互抗性弱, 对烯唑醇和异稻瘟净没有交互抗性。甲基立枯磷与二甲酰亚氨类和芳烃类杀菌剂具有相似的抑菌作用。 相似文献
4.
ABSTRACT The objective of this study was to determine the effect of silicon (Si) and rice growth stages on tissue susceptibility to sheath blight (Rhizoctonia solani Kühn) under controlled conditions. Rice plants (cv. Rio Formoso) were grown in pots containing low-Si soil amended with Si at 0, 0.48, 0.96, 1.44, and 1.92 g pot(-1) and inoculated with R. solani at the following days after emergence: 45 (four-leaf stage), 65 (eight-leaf stage), 85 (tillering), 117 (booting), and 130 (panicle exsertion). For plants inoculated with R. solani at all growth stages, Si concentration in straw increased as rate of Si increased from 0 to 1.92 g pot(-1). Concentration of calcium in the straw did not differ among plant growth stages. Although incubation period was not affected by the amount of Si added to the soil, this variable was shorter at booting and panicle exsertion stages. As the rates of Si increased in the soil, the total number of sheath blight lesions on sheaths and total area under the relative lesion extension curve decreased at all plant growth stages. The severity of sheath blight was lower at booting and panicle exsertion stages as the rates of Si increased in the soil. In general, plants grown in Si-nonamended pots and inoculated with R. solani were more vulnerable to infection at all growth stages, but especially at 45 days after emergence. Plant dry weights for inoculated plants increased as the Si rates increased from 0 to 1.92 g pot(-1). The greatest dry weight increases occurred for plants inoculated at booting and panicle exsertion stages. Si fertilization is a promising method for controlling sheath blight in areas where soil is Si deficient and when cultivars that exhibit an acceptable level of resistance to sheath blight are not available for commercial use. 相似文献
5.
Vidhyasekaran P Ponmalar TR Samiyappan R Velazhahan R Vimala R Ramanathan A Paranidharan V Muthukrishnan S 《Phytopathology》1997,87(12):1258-1263
ABSTRACT Rhizoctonia solani, the rice sheath blight pathogen, produces a toxin that reproduces all symptoms of the disease. The toxin has been partially purified and it was found to be a carbohydrate containing glucose, mannose, N-acetylgalactosamine, and N-acetylglucosamine. The toxin was also detected in infected leaves. Highly virulent isolates produced more toxin than less virulent isolates. Several R. solani isolates from rice and one each from cotton and tomato produced a similar toxin. All rice cultivars tested were susceptible to the pathogen and sensitive to the toxin. Host specificity of the toxin has been demonstrated using hosts and nonhosts of the pathogen. 相似文献
6.
蜡质芽孢杆菌AR156防治水稻纹枯病机理初探 总被引：3，自引：0，他引：3
蜡质芽孢杆菌AR156是一种防治多种土传病害的生物制剂,对水稻纹枯病具有较好的防治效果。本研究通过温室试验方面验证菌株 AR156的防病效果和促生作用,从细胞水平和基因水平初步揭示了菌株AR156防治水稻纹枯病的机理。结果表明,菌株AR156对水稻纹枯病的温室防效达73.06%,同时促进水稻生物量增加14.45%。菌株AR156处理提高了水稻植株SOD、PAL、POD和CAT等防御酶活性,增强了OsPR1b、OsPR10、OsNPR1和ZB8等防卫相关基因的表达。接种立枯丝核菌Rhizoctonia solani HNW-21之前用菌株AR156预处理的水稻植株,SOD和PAL分别提前4、2 d出现活性峰;防卫相关基因均提前表达,且表达时间延长,从而提高水稻对纹枯病的抗性。 相似文献
7.
研究了苯并噻二唑(B1H)诱发水稻产生对纹枯病的抗性。离体条件下，1．0mmol／L BTH对纹枯病菌菌丝生长无明显抑制作用。BTH叶面或灌根处理四叶一心期水稻幼苗，并将植株第2、3和4叶离体接种纹枯病菌，水稻叶片纹枯病病斑长度明显下降，BTH诱发苗期水稻产生抗性的最佳诱导期在处理后的3—5天，最佳浓度为0．1mmol／L，BTH灌根处理诱发抗性的效果较好。用BTH溶液叶面喷雾处理成株期水稻倒二叶后离体接种纹枯病菌，倒二叶、倒一叶和剑叶上病斑长度显著低于对照，最佳诱导期在处理后3—5天。用BTH处理苗期水稻第2叶或成株期倒二叶，可使未经处理的苗期水稻第3和4叶以及成株期水稻倒一叶和剑叶上纹枯病病斑长度显著下降。 相似文献
8.
双核丝核菌诱导水稻增强广谱抗病性和防卫酶系活性 总被引：16，自引：2，他引：16
用无致病性的双核丝核菌(Binucleate Rhizoctonia species,简称BNR)菌株2 32-CG预接种处理水稻品种IR2 6苗期植株根茎基部,可以诱导水稻增强对纹枯病(R.solani Kühn)的抗性。与未处理对照相比,BNR处理水稻植株的纹枯病害严重度明显降低。2 4 h以上的BNR处理,可以彻底保护幼苗不受立枯丝核菌侵染的危害。经BNR诱导的水稻也表现对白叶枯病(Xanthomonas oryzae pv.oryzae)和条斑病(X.oryzae pv.oryzicola)的抗性。BNR可以显著地诱导水稻防卫反应中的2类关键酶——苯丙氨酸解氨酶(PAL)和过氧化物酶(POX)活性提高。受BNR诱导的抗病性与PAL和POX活性呈正相关。对BNR在水稻病害生物防治中的作用进行了讨论。 相似文献
9.
The mode of action of acibenzolar-S-methyl (BTH) was investigated against sheath blight of rice and its pathogen, Rhizoctonia solani. BTH exhibited limited fungitoxicity against R solani, in the form of reduced mycelial growth, hyphal browning and sclerotia formation. Parasite fitness of mycelia and sclerotia formed on BTH-amended media was also reduced. When applied as soil drench or foliar spray, BTH inhibited both disease development on inoculated sheaths and its spread to the younger sheaths. The degree of protection against sheath blight increased with increase in duration between BTH application and inoculation. The curative effect of BTH was poor. When applied through roots a protective effect of BTH was visible even with only a 1-h interval between application and inoculation. However, in the case of foliar application, protective effect was recorded only when the gap between application and inoculation was 24 h. BTH reduced the frequency of penetration by R solani, colonization of host tissue and spread of the hyphae from primary lesions to form secondary lesions. BTH induced swelling of hyphal tips on the sheath surface, formation of papillae, browning of penetrated epidermal cells and degeneration of intra-cellular hyphae colonizing epidermal and mesophyll cells. Therefore, the protective effect of BTH against sheath blight was due to combination of its host defence-inducing activity and its adverse effect on growth and vigor (parasite fitness) of the pathogen. 相似文献
10.
我国南方稻区水稻骨干亲本纹枯病抗性鉴定与分析 总被引：3，自引：0，他引：3
运用改进的纹枯病菌接种法,对当前我国南方稻区17个骨干亲本纹枯病抗性进行了田间鉴定,测定和分析了各材料的纹枯病病级(RD)、相对病斑高度(HR)及株高(HP)。通过试验,将17个骨干亲本分为抗病、中等抗病、中等感病和感病4种类型;筛选出了3个抗病亲本(明恢63、蜀恢527、广恢128)和3个中抗亲本(绵恢725、珍汕97B和协青早B);供试亲本的平均RD为4.78,平均HR为0.52;通过分析,发现纹枯病病级(RD)和相对病斑高度(HR)呈极显著正相关(y=8.373x+0.435,y=RD;x=HR)、株高和病级相关不显著。 相似文献
11.
Pathotypic and genetic diversity in the population of Rhizoctonia solani AG1‐IA causing rice sheath blight in China 
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下载免费PDF全文 Sheath blight, caused by Rhizoctonia solani AG1‐IA, is one of the most serious diseases of rice. In this study, a total of 175 isolates of R. solani AG1‐IA were collected from five rice‐growing regions in China. Pathogenicity tests revealed that all isolates were virulent to five cultivars with different levels of resistance at the rice seedling stage in the greenhouse. There was considerable variation in aggressiveness, and the isolates were classified into three pathotypes based on disease severity, with moderately virulent isolates prevalent in the population. Forty‐three haplotypes were identified based on ITS sequencing, and 39 haplotypes were distinct among isolates. There were high levels of haplotype diversity and nucleotide diversity within the populations of R. solani AG1‐IA. High gene flow (Nm = 1·63–5·22) was detected, consistent with relatively low differentiation between pairs of populations. Five populations were divided into two distinct clusters by the unweighted pair group method with arithmetic mean (UPGMA), and no spatial population differentiation was discernible. The majority (97·8%) of genetic diversity was distributed among isolates within populations, with only 2·2% of the genetic diversity attributed to differences among populations. The star‐like shape of the haplotype network provided evidence of signatures of population expansion in recent history. No significant relationships were found between the genetic diversity and aggressiveness or geographic origin among populations of R. solani AG1‐IA. These results highlight that the population characteristics of R. solani AG1‐IA should be taken into account in evaluating the germplasm resistance of rice cultivars to sheath blight. 相似文献
12.
Establishment methods for rice crops in tropical Asia are very diverse, leading to variation in the structure of rice canopies. Differences in canopy structure can in turn affect the spread of the rice sheath blight pathogen, Rhizoctonia solani . Rice sheath blight epidemics were compared during two seasons in crops established by different methods: direct broadcasting of pregerminated rice seeds, and transplanting of rice seedlings at spacings of 20 × 20 cm, 13 × 25 cm and 25 × 25 cm between hills (i.e. along and between rows, respectively). In both years, the apparent infection rate based on incidence data and the terminal severity of sheath blight were lower in the direct-seeded crops than in any of the transplanted ones, regardless of spacing. The frequency of leaf-to-leaf contacts ( CF ) between hills (or plants) was highest in direct-seeded rice, and lowest in rice transplanted at a spacing of 25 × 25 cm. Larger CF is known to favour rice sheath blight epidemics. The apparent contradiction between higher incidence and lower CF in the transplanted stands than in the direct-seeded stands is interpreted in terms of accessibility of healthy host tissues to the spread of the pathogen in the canopy, and accounts for within-host (rice hill or plant) and between-host (hill or plant) disease spread. The analysis of incidence-severity relationships indicated a less aggregated distribution of the disease in direct-seeded rice, which was related to the spatial distribution of the tillers. These findings have direct implications for the management of the disease. 相似文献
13.
丙环唑对水稻纹枯病菌的抑制作用及对纹枯病的防治效果 总被引：5，自引：0，他引：5
为明确丙环唑对水稻纹枯病的防治作用,通过离体抑菌试验,温室盆钵试验和田间试验研究了丙环唑对水稻纹枯病菌的抑制作用和对纹枯病的防治效果.离体抑菌试验表明,丙环唑能够强烈抑制水稻纹枯病菌(Rhizoctonia solani)的菌丝生长,EC50为0.045 μg/mL,并能够强烈抑制菌核产生,但不能抑制菌核萌发.温室试验表明,纹枯病菌经丙环唑处理后,致病力随药剂浓度提高而显著减弱;丙环唑可以很好地被水稻叶片和根系吸收,并输送到水稻的茎部和叶鞘;丙环唑对水稻纹枯病具有保护和治疗作用,400 μg/mL丙环唑处理水稻,抑制病斑长度分别达到82.16％和76.61％,并随药剂处理浓度的降低而降低;丙环唑对立枯丝核菌有较长的持效期,800 μg/mL处理水稻11 d后再接种的防效为40.10％.田间药效试验表明,25％的丙环唑乳油在有效剂量150 g/hm2下3次喷药后14 d的防效达到89.15％,丙环唑在本试验剂量范围内对水稻安全.表明丙环唑对水稻纹枯病有很好的防治作用,可为生产上防治水稻纹枯病和科学用药提供依据. 相似文献
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15.
为明确中国东北地区水稻纹枯病病原菌种类及融合群的归属情况, 2015－2017年从黑龙江省、吉林省和辽宁省的17个水稻主产区采集水稻纹枯病标样, 分离获得水稻纹枯病菌214株, 运用水稻纹枯病菌的不同病原菌及融合群的特异性引物对214株水稻纹枯病菌进行病原菌种类和融合群鉴定, 并利用rDNA内转录间隔区(ITS)序列, 对供试水稻丝核菌的融合群归属进行了分析。结果表明:供试214株水稻纹枯病菌分属于茄丝核菌Rhizoctonia solani和水稻丝核菌Rhizoctonia oryzae-sativae, 菌株数分别为198株和16株, 占比分别为92.52%和7.48%。茄丝核菌菌株分属于2个融合群, 分别为AG1-IA和AG4, 菌株数分别为191株和7株, 占比分别为96.46%和3.54%。水稻丝核菌菌株均属于AG-Bb融合群, 菌株数为16株。不同年份水稻纹枯病的病原菌种类及融合群出现的频率和地域分布无明显变化, 而不同地域间水稻纹枯病病原菌的种类及融合群具有明显的分化特征, AG1-IA融合群在中国东北三省各个水稻产区均有分布且均为优势融合群, AG4融合群在辽宁省盘锦市出现频率最高, 水稻丝核菌AG-Bb融合群在吉林省吉林市、通化市和梅河口市出现频率最高。 相似文献
16.
分别从未使用过噻呋酰胺及使用噻呋酰胺3年以上的浙江省稻田采集分离立枯丝核菌Rhizoctonia solani，通过监测、分析病原菌群体对噻呋酰胺的敏感性变化，研究了立枯丝核菌对噻呋酰胺的抗药性风险；并以戊唑醇、井冈霉素等纹枯病防治常用药剂为对照，通过田间试验评价了噻呋酰胺油悬浮剂 (OD) 对稻田天敌群落的影响。结果表明:浙江省未接触过噻呋酰胺的立枯丝核菌群体 (n = 164) 的EC50值分布在 0.008~0.135 mg/L 之间，且呈近似正态单峰曲线，平均EC50值为 (0.073 ± 0.005) mg/L，可作为立枯丝核菌对噻呋酰胺的敏感性基线，用于后续田间抗药性监测。接触过噻呋酰胺3年以上的立枯丝核菌群体 (n = 130) 的EC50值分布在 0.009~0.126 mg/L之间，平均EC50值为 (0.069 ± 0.080) mg/L，未观察到明显的敏感性下降。对稻田天敌群落影响的田间试验表明，采用12%噻呋酰胺油OD处理 7 d 后，绍兴稻田的 Shannon多样性指数和丰富度指数均显著高于清水对照（CK），而其他时间和地点均与CK无显著性差异。研究表明，采用噻呋酰胺防治水稻纹枯病的田间抗药性风险低，对稻田天敌安全性高。 相似文献
17.
B. Tar’an T. Warkentin A. Tullu A. Vandenberg 《European journal of plant pathology / European Foundation for Plant Pathology》2007,119(1):39-51
Breeding for resistance to ascochyta blight in chickpea has been challenged by several factors including the limited sources
of good resistance. Characterization of a set of genotypes that may contain different genes for resistance may help breeders
to develop better and more durable resistance compared to current cultivars. The objective of this study was to evaluate the
genetic relationships of 37 chickpea germplasm accessions differing in reaction to ascochyta blight using Simple Sequence
Repeat (SSR) markers linked to Quantitative Trait Loci (QTL) for resistance. The results demonstrated that ILC72 and ILC3279,
landraces from the former Soviet Union, had SSR alleles that were common among the kabuli breeding lines and cultivars. A
lower SSR allele diversity was found on LG4 than on other regions. No correlation was found between the dendrogram derived
using SSRs at the QTL regions and the SSRs derived from other parts of the genome. The clustering based on 127 alleles of
17 SSRs associated with the QTL for ascochyta blight resistance enabled us to differentiate three major groups within the
current germplasm accessions. The first group was the desi germplasm originating from India and cultivars derived from it.
The second group was a mix of desi genotypes originating from India and Greece, and kabuli breeding lines from ICARDA and
the University of Saskatchewan. The third and largest group consisted of landraces originating mostly from the former Soviet
Union and breeding lines/cultivars of the kabuli type. Several moderately resistance genotypes that are distantly related
were identified. Disease evaluation on three test populations suggested that it is possible to enhance the level of resistance
by crossing moderately resistant parents with distinct genetic backgrounds at the QTL for resistance to ascochyta blight. 相似文献
18.
Cecilia B PASCUAL Avelino D RAYMUNDO Mitsuro HYAKUMACHI 《Journal of General Plant Pathology》2000,66(1):23-29
Sorghum line CS 621 was evaluated along with other lines and cultivars for resistance to Rhizoctonia sheath blight, tar spot and gray leaf spot for 3 years. CS 621 was consistently resistant to these diseases even under a
heavy natural outbreak of tar spot in the breeding nursery. It was also found to be more resistant to Rhizoctonia sheath blight than the resistant lines from Japan during the 1993 to 1994 screening tests. Resistance to Rhizoctonia solani AG1-IA was expressed in the form of reduction in the severity of disease and rate of infection. Evaluation of progenies from
crosses involving CS 621 and a susceptible variety, UPL Sg5, indicated that additive and dominant gene effects are important
in the expression of quantitative resistance to R. solani. CS 621 could therefore serve as a source of multiple resistance genes in a breeding program for high yield and stability
against sorghum diseases.
Received 6 August 1999/ Accepted in revised form 18 October 1999 相似文献
19.
两个玉米自交系对纹枯病的抗病反应机制初探 总被引：1，自引：0，他引：1
玉米纹枯病是由立枯丝核菌(Rhizoctonia solani Kühn)引起的一种重要病害。具有优良性状的自交系是开展玉米抗病品种选育的重要种质资源。本试验以西南地区两个优良玉米自交系R08与18-599R为材料,采用人工接种R.solani菌丝融合群AG1-IA,对成株期玉米进行了抗性鉴定,并对病原菌诱导后苗期玉米叶片上的活性氧(ROS)、抗病相关基因(PR1、ZmDREB2A、ZmERF3和WIP1)表达及细胞坏死情况进行了动态检测。结果显示,R08对纹枯病表现为中抗,而18-599R为高感材料;受R.solani侵染后,玉米叶片ROS的积累在R08中较18-599R多;两个自交系中基因表达量及表达时间存在显著差异;R08叶片出现显著的细胞坏死反应,而18-599R相对较轻。本研究表明两个自交系对R.solani的抗性差异主要体现在相关抗病反应的时间和强度上,这为进一步研究玉米纹枯病抗病机理提供了依据。 相似文献
20.
戊唑醇是一种高效、广谱、内吸性强的三唑类杀菌剂。研究表明,在离体条件下其对立枯丝核菌Rhizoctonia solani Kuhn菌丝生长具有很强的抑制作用,EC50值为0.509 μg/mL。无论在天然培养基(LBA)还是在半组合培养基(AEA)上,戊唑醇均会抑制菌核的产生,且菌核的产量随着药剂浓度的增加而降低;虽然其对菌核的萌发无影响,但对菌核萌发后菌丝的生长有强烈的抑制作用。温室试验结果表明,立枯丝核菌菌碟经戊唑醇处理后,其对分蘖期水稻植株的致病力随着药剂浓度的提高而下降;戊唑醇可很好地被水稻叶片和根系吸收,并输送到水稻的茎部;对水稻纹枯病具有保护和治疗作用,EC50值分别为58.03和62.53 μg/mL;对立枯丝核具有较长的持效期,800 μg/mL处理水稻7 d后再接种的防效为41.46%。田间药效试验表明,43%的戊唑醇悬浮剂在有效剂量116.10 g/hm2下两次喷药后15 d的防效达71.97%。该药剂在本试验剂量范围内对水稻安全。 相似文献